Description: 【2 IN 1 Transmitter and Receiver】Cordless aux adapter supports both transmit and receive, TX RX modes, easily and simply upgrade your old speakers or car audio system to compatible cordless audio. 【Stable Connection】With upgraded 5.0 technology, the wireless transmitter receiver can reduce power consumption and provide fast and stable transmission. 【Easy to Use】The headphone transmitter receiver is easy to install and use. Just plug the aux adapters into the AUX port of the receiver or transmitter, then press for 3 seconds to power on and ready to pair. 【Wide Compatibility】This transmitter receiver is compatible with devices with 3.5mm interface, the receiver mode is used for car audio, wired speaker, home speaker, speaker amplifier, earphones, etc., and the transmitter mode is suitable for computers, projection instruments, power amp, headphones, speakers, etc. 【Portable Size】The compact design of this transmitter and receiver saves you space, easy to carry, approx 10cmx4.9cmx2.4cm/3.94inchx1.93inchx0.94inch Specification: Interface type : AUX / RCA / USB / TF Battery capacity : 3.7V / 400mAh battery Signal to noise ratio : >90db Size Chart: approx 10cmx4.9cmx2.4cm/3.94inchx1.93inchx0.94inch Package Includes: 1 Transmitter Receiver 1 AUX Cable 1 Charging Cable Note: Please allow slightly errors due to manual measurement and different monitors.